1. Department of Chemical Technology of Plastics Processing, Lviv Polytechnic National University, 12, St. Bandera Str., 79013 Lviv, Ukraine
2. Department of Heat Engineering and Thermal and Nuclear Power Plants, Lviv Polytechnic National University, 12, St. Bandera Str., 79013 Lviv, Ukraine
3. Department of Technologies, Materials and Computer Aided Production, Faculty of Mechanical Engineering, Technical University of Košice, 74 Mäsiarska, 04001 Košice, Slovakia